The invention relates to magnets, and more particularly to nanocomposite permanent magnets and methods of making the same.
Permanent magnets are used in a wide variety of fields, including electronics, industrial and electric motors. Growing global demand for high efficiency electric machines, such as electric motors and generators, has correspondingly increased the demand for high efficiency permanent magnets. For example, magnets with higher energy products facilitate making relatively compact electric machines that have relatively higher power densities.
Generally, permanent magnets are made from compounds of rare earth metals such as Nd2Fe14B, SmCo5 and Sm2Co17. Usually, these compounds of the rare earth metals may contain small percentages of other rare earth metals. For example, small percentages of dysprosium and terbium may be added to the permanent magnets to enhance intrinsic coercivity of the permanent magnets. The permanent magnets with enhanced intrinsic coercivity may demonstrate enhanced performance at high temperatures. However, as will be appreciated, the rare earth metals have been identified as critical elements due to their limited supply in the face of increasing demand. A rapid rise in the cost of the rare earth metals poses challenges in making the rare earth containing magnets viable candidates for bulk use, such as industrial applications.
Therefore, it is desirable to provide economically feasible permanent magnets that contain relatively lower amounts of rare earth metals.